Oxidizing processes of organic substrates by the use of molecular oxygen as an oxidizing agent, in particular those for oxidizing alcohols to obtain the corresponding carbonyl compounds, are very important in industries of organic chemistry, from the viewpoint of economy and of protecting environment.
Separately, processes for the oxidation of alcohols using a ruthenium compound as a catalyst to give carbonyl compounds have been investigated in different ways. By way of illustration, in J. Chem. Soc., Chem. Commun., 1987, 1625 is proposed a process for the oxidation of an alcohol to give the corresponding carbonyl compound by the use of a catalytic amount of tetrapropylammonium perruthenate and 1.5 equivalents of 4-methylmorpholine-N-oxide with respect to the alcohol. In Bull. Chem. Soc. Jpn., 61, 3607(1988) is proposed a process for the oxidation of allyl alcohol and benzyl alcohol using dichlorotris(triphenylphosphine)ruthenium(II) and two equivalents of bis (trimethylsilyl)peroxide with respect to the alcohols. These processes, however, require large amounts of co-oxidizing agents such as peroxides which need careful handling, and are economically disadvantageous.
In J. Am. Chem. Soc., 1997, 12661 is disclosed a process for the oxidation of an alcohol by molecular oxygen in the presence of a catalytic amount of tetrapropylammonium perruthenate and a molecular sieve to obtain a carbonyl compound. This process, however, requires comparatively large amounts of molecular sieves. In addition, a secondary alcohol is more liable to be oxidized than a primary alcohol in such oxidation reactions of alcohols by oxygen, and such a primary alcohol can hardly be oxidized in a selective manner (see J. Chem. Soc., Chem. Commun., 1994, 1037).